In a machining line, a semiconductor manufacturing apparatus, or an electronic component mounting apparatus, a robot driving device is incorporated for gripping and conveying work pieces such as materials to be processed, wafers, substrates, or the like. The robot driving device has a robot for handling work pieces for example, which is mounted on a traveling carriage that reciprocates on a track. By operating a hand of an arm of the robot, a work piece may be gripped by the hand, and then the work piece may be attached to and detached from each processing machine.
An electric cable, an optical cable, a tube for supplying hydraulic or pneumatic power or the like (hereinafter, referred to as a “cable”) is connected to the traveling carriage of the robot driving device. Since the traveling carriage continuously reciprocates such that a position of the traveling carriage is varied, it is required to steadily move the cable along with the traveling carriage so that the cable follows the variation in position of the traveling carriage. For this reason, for example, a multi-joint type cable support member called Cable Bear (registered trademark) is known which allows a cable to follow the variation in position of the traveling carriage by bending the cable having a given length to be curved in a U shape to support the cable and changing the lengths of the opposite legs of the U shape.
Such a cable support member, which is bendable in a U shape, is disclosed in Japanese Patent No. 4658221. The cable support member (multi-joint support member) disclosed in Japanese Patent No. 4658221 is constituted by a series of synthetic resin block bodies connected by pin couplings. Further, in Japanese Patent No. 4658221, the cable support member is inserted through and integrally clamped to a flexible belt member, which is provided with a plurality of conduits in parallel arrangement, together with cables so that a multi joint type protective guide device for the cable is configured. In addition, the support member may be bent to a given radius of curvature based on the shapes of the block bodies, while a horizontally straight state of the support member is maintained against gravity, or the support member is prevented from being curved to be convex downward.
A cable support member, which is bendable in a U shape, is also disclosed in Japanese Patent No. 4157096. In Japanese Patent No. 4157096, the cable support member is constituted by a belt-shaped stainless steel strip (a flexible material) having a spring property, and a series of synthetic resin holding members (a non-interlocking solid material) fixed to the stainless steel strip by an injection molding. Further, a cable support structure, in which the cable support member is inserted through and integrally clamped to the a plurality of channels in parallel arrangement, together with cables, is disclosed in FIG. 21 or the like of Japanese Patent No. 4157096.
While the series of synthetic resin block bodies in the cable support member of Japanese Patent No. 4658221, including pins used for connection, may be comparatively simply manufactured by an injection molding, it is necessary to fit all the pins of the plurality of synthetic resin block bodies into corresponding holes when connecting the synthetic resin block bodies. Therefore, the assembling property thereof may not be necessarily good. Further, a dimension in an axial direction (longitudinal direction of the cable) becomes longer due to a space required to connect the synthetic resin block bodies to each other with the pins, and thus, there is a problem in that a possible minimum radius of curvature when the cable support member is bent, and therefore a space required for wiring may not be reduced.
The holding member (non-interlocking solid material) of the cable support member of Japanese Patent No. 4157096 is fixed to the stainless steel strip by the injection molding. However, in the case of this structure, a portion of the stainless steel strip, which is fixed to the holding member, does not effectively act as a spring. This matter becomes a disadvantageous factor when designing a spring of the stainless steel strip, and thus there is a concern in that sufficient fatigue strength may not be obtained. Further, the process of injection molding of the holding members to the stainless steel strip is recognized as a factor that degrades productivity.
Further, the cable support members of Japanese Patent Nos. 4658221 and 4157096 may be moved in one direction within a certain range, but absolutely may not be moved in the opposite direction, which is opposite to the one direction, due to an operation of a stopper. For this reason, in a case in which a load in the opposite direction is applied to the cable support member, there is a concern in that in the cable support member of Japanese Patent No. 4658221 pin coupling portions of the synthetic resin block bodies are damaged, or in the cable support member of Japanese Patent No. 4157096 the stainless steel strip (flexible material) and the holding member (non-interlocking solid material) are separated and damaged.